brahmanda

Brahmanda (Sanskrit: ब्रह्माण्ड — the cosmic egg, the universe)

Large-scale structure physics — galaxy morphology, dark matter halos, cosmic web topology, and structure formation. Part of the AGNOS science stack, built on hisab.

Features

Cosmology (cosmology)

Parameterized cosmology with presets (Planck 2018, WMAP9). All computations take &Cosmology for full flexibility.

Galaxy Morphology (morphology)

Hubble classification, Sersic surface brightness profiles, Faber-Jackson (elliptical) and Tully-Fisher (spiral) scaling relations, mass-metallicity relation, Madau-Dickinson SFR density.

Dark Matter Halos (halo)

NFW density profiles, enclosed mass, circular velocity curves, virial radius, concentration-mass (Dutton & Maccio 2014). Mass functions (Press-Schechter, Sheth-Tormen, Tinker 2008), halo bias (Mo-White, ST, Tinker 2010), mass accretion history, SHAM.

Cosmic Web (cosmic_web)

Tidal tensor eigenvalue classification (node/filament/sheet/void), density contrast, correlation function, void profiles, Hessian morphology, Minkowski functionals.

Power Spectrum (power_spectrum)

Eisenstein-Hu transfer function (with BAO), exact sigma(R) integration, linear P(k) normalized to sigma_8, Halofit nonlinear P(k), growth factor & rate, dark energy EoS, distances (comoving, luminosity, angular diameter), lookback time, age of universe, angular C_l, Sachs-Wolfe.

Quick Start

use brahmanda::{Cosmology, halo::HaloProperties};

let cosmo = Cosmology::planck2018();

// Milky Way-mass dark matter halo
let halo = HaloProperties::from_mass(1e12, &cosmo).unwrap();
println!("Virial radius: {:.0} kpc", halo.r_vir_kpc);       // ~250 kpc
println!("Concentration: {:.1}", halo.concentration);         // ~8

use brahmanda::{Cosmology, power_spectrum};

let cosmo = Cosmology::planck2018();

// Growth factor and age of the universe
let d = power_spectrum::growth_factor(1.0, &cosmo).unwrap();
let age = power_spectrum::age_of_universe(0.0, &cosmo).unwrap();
println!("D(z=1) = {d:.4}, age = {age:.1} Gyr");

use brahmanda::cosmic_web;

// Classify a cosmic web environment from tidal tensor eigenvalues
let env = cosmic_web::classify_web_environment(&[2.0, 1.0, 0.5], 0.0).unwrap();
assert_eq!(env, cosmic_web::WebEnvironment::Node);

Relationship to AGNOS Science Stack

hisab (math foundation)
  ├── hisab-mimamsa — theoretical physics (GR, QFT, cosmology, unified)
  │     └── unified::scale_bridge — Scale 5 consumes brahmanda outputs
  ├── brahmanda (this) — galactic / large-scale structure
  ├── tara — stellar astrophysics
  ├── jyotish — astronomical computation
  └── falak — orbital mechanics

License

GPL-3.0-only

Contributing

See CONTRIBUTING.md for guidelines.